Camera control apparatus

ABSTRACT

A camera control apparatus is provided. The camera control apparatus includes: a processor configured to detect a partial image including an object from a first image of a camera, generate a control value for controlling a camera capturing area to position a specific point of the object corresponding to specific coordinates of the partial image on center coordinates of a second image of the camera which is captured by the camera subsequent to the first image based on center coordinates of the partial image and center coordinates of the first image; and a camera drive controller configured to change the camera capturing area based on the control value output from the processor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Korean Patent Application No.10-2014-0065108, filed on May 29, 2014 in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

Apparatuses and methods consistent with exemplary embodiments relate toa camera control apparatus which makes an object included in a cameraimage acquired by capturing an image of a monitoring area be positionedin a center of the camera image.

2. Description of the Related Art

A pan-tilt-zoom (PTZ) camera is used to accurately capture an image ofan object in a monitoring area.

The PTZ camera includes pan, tilt, zoom, and focus functions to track anobject through a movement of a camera or to enlarge or precisely capturean image of the object.

However, since the PTZ camera in the related art tracks or preciselycaptures the image of the object through execution of any one of pan,tilt, zoom, and focus functions after forming a camera image that isacquired by capturing the image of the monitoring area, a delayphenomenon occurs in tracking the object due to the performing of thetracking after capturing the image of the object.

Accordingly, due to the delay phenomenon in tracking the object asdescribed above, the object included in the camera image is positionedat a point that secedes from the center of the camera image.

SUMMARY

Exemplary embodiments address at least the above problems and/ordisadvantages and other disadvantages not described above. Also,exemplary embodiments are not required to overcome the disadvantagesdescribed above, and an exemplary embodiment may not overcome any of theproblems described above

One or more exemplary embodiments include a camera control apparatus,which makes an object included in a camera image acquired by capturingan image of a monitoring area be positioned in a center of the cameraimage.

Various aspects will be set forth in part in the description whichfollows and, in part, will become apparent to those having ordinaryskill in the art upon examination of the following or may be learnedfrom practice of the exemplary embodiments.

According to an aspect of an exemplary embodiment, there is provided acamera control apparatus including: a processor configured to detect apartial image including an object from a first image of a camera,generate a control value for controlling a camera capturing area toposition a specific point of the object corresponding to specificcoordinates of the partial image on center coordinates of a second imageof the camera which is captured by the camera subsequent to the firstimage based on center coordinates of the partial image and centercoordinates of the first image; and a camera drive controller configuredto change the camera capturing area based on the control value outputfrom the processor.

The processor may include an image reception module configured toreceive a camera image in a frame unit; a target detection moduleconfigured to detect the partial image through a user's selection or apredetermined image detection process; a control value calculationmodule configured to determine control center coordinates for the cameracapturing area as a specific point in an opposite direction to thecenter coordinates of the partial image based on a difference betweenthe center coordinates of the partial image and the center coordinatesof the first image, change a weight of a control acceleration forchanging the camera capturing area according to a difference between thecenter coordinates of the partial image and the control centercoordinates, and to generate the control value based on the changedweight; and a control execution module configured to output the controlvalue to the camera drive controller.

The camera control apparatus may further include an input unit to selectthe partial image.

The control value calculation module is configured to determine whethera speed reduction pattern of an acceleration of the object exists, andset a camera speed reduction section before a stop expectation point ofthe object if it is determined that the speed reduction pattern exists.

If it is determined that the speed reduction pattern does not exist, thecontrol value calculation module is configured to set the camera speedreduction section based on a stop point of the object during a stop ordirection change of the object, and set to move camera in a reversedirection at a predetermined reference speed as long as a distancebetween the center coordinates of the second image and the specificpoint of the object.

If a plurality of objects exist in the first camera image, the targetdetection module is configured to select any one of the plurality ofobjects by a user selection.

If a plurality of objects exist in the first camera image, the targetdetection module is configured to automatically select any one of theplurality of objects based on a predetermined selection priority, inwhich an object having high possibility of seceding from a monitoringarea is set as a priority object.

The control value calculation module is further configured to includeparameters for applying a field of view (FOV) value corresponding to azoom magnification of the second image to the weight change of thecontrol acceleration.

According to an aspect of another exemplary embodiment, there isprovided a method of controlling a camera control apparatus including:receiving a camera image in a frame unit from a camera; detecting apartial image including an object from a first image of a camera;generating a control value for controlling a camera capturing area toposition a specific point of the object corresponding to specificcoordinates of the partial image on center coordinates of a second imageof the camera which is captured by the camera subsequent to the firstimage based on center coordinates of the partial image and centercoordinates of the first image; and changing the camera capturing areabased on the generated control value.

Accordingly to an aspect of another exemplary embodiment, there isprovided a non-transitory computer readable medium having recordedthereon a program, which, when executed by a computer, performsabove-recited method.

BRIEF DESCRIPTION OF DRAWINGS

The above and/or other aspects will be more apparent from the followingdetailed description of the exemplary embodiments, taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating a camera control apparatusaccording to an exemplary embodiment;

FIG. 2 is a block diagram illustrating a configuration of a processorshown in FIG. 1, according to an exemplary embodiment;

FIG. 3 is a block diagram illustrating a camera control apparatusaccording to an exemplary embodiment;

FIG. 4 is a diagram illustrating a camera image captured by a camera,according to an exemplary embodiment;

FIG. 5 is an exemplary diagram illustrating an image screen in theprocess of moving an object in the camera image of FIG. 4 to the centerof a screen, according to an exemplary embodiment;

FIGS. 6 to 8 are exemplary diagrams illustrating the image screen ofFIG. 5 by time zones;

FIG. 9 is a flowchart illustrating an operation of the processor shownin FIG. 1 according to an exemplary embodiment;

FIG. 10 is a flowchart of operation S104 shown in FIG. 9, according toan exemplary embodiment;

FIG. 11 is an exemplary diagram illustrating an image screen of anobject which is in a standstill state or of which the direction ischanged in the camera image of FIG. 4, according to an exemplaryembodiment;

FIG. 12 is a flowchart illustrating a process subsequent to “K” shown inFIG. 10, according to an exemplary embodiment;

FIG. 13 is an exemplary diagram illustrating camera images captured by acamera, which are discriminated by control directions;

FIG. 14 is an exemplary diagram illustrating an example in which anobject is specified if a plurality of objects exist in a camera imagecaptured by a camera;

FIG. 15 is a flowchart illustrating an operation of the camera controlapparatus of FIG. 1 according to an exemplary embodiment;

FIG. 16 is an exemplary diagram illustrating another example in which anobject is specified if a plurality of objects exist in a camera imagecaptured by a camera;

FIG. 17 is a flowchart illustrating an operation of the camera controlapparatus according to an exemplary embodiment;

FIG. 18 is a flowchart illustrating an operation of the camera controlapparatus according to an exemplary embodiment;

FIG. 19 is an exemplary diagram illustrating a case where objects recedein the distance in camera images captured by a camera;

FIG. 20 is an exemplary diagram illustrating zoom-in camera images ofFIG. 19;

FIGS. 21A and 21B are exemplary diagrams illustrating respective imagesthat are obtained by discriminating camera images of FIG. 4 according tofields of view; and

FIG. 22 is a graph illustrating an example of an acceleration changeaccording to a zoom change.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, various exemplary embodiments will be described in detailwith reference to the accompanying drawings. The matters defined in thedescription, such as detailed construction and elements, are provided toassist in a comprehensive understanding of the exemplary embodiments.Thus, it is apparent that the exemplary embodiments can be carried outwithout those specifically defined matters. Like reference numeralsrefer to like elements throughout the specification.

The terminology used herein is describing the exemplary embodiments andis not intended to limit the inventive concept. As used herein, thesingular terms “a”, “an” and “the” are intended to include the pluralforms as well, unless otherwise specified. It will be understood thatthe terms “comprises” and/or “comprising,” when used in thisspecification, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

It will be understood that when an element or layer is referred to asbeing “on”, “connected to” or “coupled to” another element or layer, itcan be directly on, connected or coupled to the other element or layeror intervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on”, “directly connected to”or “directly coupled to” another element or layer, there are nointervening elements or layers. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

It will be understood that, although the terms “first”, “second”, etc.may be used herein to describe various elements, components, regions,layers and/or sections, these elements, components, regions, layersand/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer orsection from another region, layer or section. Thus, a first element,component, region, layer or section discussed below could be termed asecond element, component, region, layer or section without departingfrom the teachings of the inventive concept.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”,“upper”, and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. In other words, the device may beotherwise reoriented (e.g., rotated 90 degrees or at other orientations)and the spatially relative descriptors used herein interpretedaccordingly.

Exemplary embodiments are described herein with reference tocross-section illustrations that are schematic illustrations ofidealized embodiments (and intermediate structures). As such, variationsfrom the shapes of the illustrations as a result, for example, ofmanufacturing techniques and/or tolerances, are to be expected. Thus,the exemplary embodiments should not be construed as limited to theparticular shapes of regions illustrated herein but are to includedeviations in shapes that result, for example, from manufacturing. Forexample, an implanted region illustrated as a rectangle will, typically,have rounded or curved features and/or a gradient of implantconcentration at its edges rather than a binary change from implanted tonon-implanted region. Likewise, a buried region formed by implantationmay result in some implantation in the region between the buried regionand the surface through which the implantation takes place. Thus, theregions illustrated in the figures are schematic in nature and theirshapes are not intended to illustrate the actual shape of a region of adevice and are not intended to limit the scope of the inventive concept.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which the inventive concept belongs. Itwill be further understood that terms, such as those defined in commonlyused dictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andthis specification and will not be interpreted in an idealized or overlyformal sense unless expressly so defined herein.

FIG. 1 is a block diagram illustrating a camera control apparatusaccording to an exemplary embodiment.

Referring to FIG. 1, a camera control apparatus 100 is so configuredthat an object included in a camera image acquired by capturing an imageof a monitoring area be always positioned in the center of the cameraimage, and thus can greatly reduce the possibility that an objectpositioned at an edge of the camera image is lost due to a non-reactionto an abrupt speed change of the object or the like.

In addition, it is preferable, but not necessary, that the cameracontrol apparatus 100 is configured so as to remove a screen vibrationphenomenon that occurs in the center portion of the camera image due toinertia of movement of a camera that is caused by a camera stop when theobject being tracked is stopped or changes its direction aftercontrolling the movement of the camera through increasing of the movingspeed of the camera to make the object be always positioned in thecamera image.

The camera control apparatus 100 may include a processor 120 and acamera drive controller 130.

For the purpose of efficiently tracking an object in a monitoring area,a camera (not illustrated) that interlocks with the camera controlapparatus 100 may be provided as a PTZ camera having pan, tilt, zoom,and focus functions.

The processor 120 detects a partial image including the object from afirst image of the camera provided from the camera, and generates acontrol value for positioning a specific point of the objectcorresponding to specific coordinates of the detected partial image onthe center coordinates of a second image of the camera which is capturedby the camera subsequent to the first image.

The partial image including the object may be detected from the firstimage by a user's selection or through a predetermined image detectionprocess.

The partial image including the object may be automatically detectedfrom the first image through the predetermined image detection processwithout user's participation.

For example, a camera image of a current frame and a camera image of aprevious frame may be compared with each other, a cell area including anobject as a target of observation may be specified based on differentpoints between the images as a result of comparison, and a specific cellarea may be determined as the partial image as described above.

As another example, a face recognition algorithm may be executed withrespect to a camera image of the current frame, a cell area including anobject as a target of observation may be specified based on a result ofthe face recognition, and a specific cell area may be determined as thepartial image as described above.

The processor 120 and the camera drive controller 130 may be integrallyprovided with the camera or may be provided as a separate configurationfrom the camera.

If the processor 120 is provided as a separate configuration from thecamera, a control of a single camera may be performed in directinterlocking with the camera through a wired or wireless connection, anda control of a plurality of cameras may be performed through networkconnections (e.g., home network, Internet, and heterogeneous network)with the plurality of cameras including the camera.

The camera drive controller 130 changes a capturing area of the camerabased on the control value output from the processor 120.

FIG. 2 is a block diagram illustrating a configuration of the processor120 shown in FIG. 1.

Referring to FIG. 2, the processor 120 may include an image receptionmodule 121 configured to receive a camera image in a frame unit from thecamera, a target detection module 123 configured to detect a partialimage from a first image of the camera through a predetermined imagedetection process, a control value calculation module 125 configured todetermine a specific point of the first image corresponding to thecenter coordinates of the partial image based on the center coordinatesof the first image as control center coordinates of the camera, tochange a weight of a control acceleration for movement control of thecamera according to a difference between the center coordinates of thepartial image and the control center coordinates of the camera, and togenerate the control value for movement of the camera based on thechanged weight, and a control execution module 127 configured to outputthe generated control value to the camera drive controller 130.

FIG. 3 is a block diagram illustrating a camera control apparatus 200according to an exemplary embodiment.

Referring to FIG. 3, the camera control apparatus 200 may include aninput unit 240, a processor 220, and a camera drive controller 230.

The input unit 240 may enable a user to select a partial image includingan object from a camera image.

The processor 220 detects a partial image including the object from afirst image provided from the camera through a user setting signal thatis transferred from the input unit 240, and generates a control valuefor positioning a specific point of the object corresponding to specificcoordinates of the partial image on the center coordinates of a secondimage of the camera which is captured by the camera subsequent to thefirst image.

The detection of the partial image from the first image through a user'sselection is performed by selecting a specific point at which the objectis positioned from the first image through a user's touch or a userinput means, such as a cursor, and designating a surrounding group cellaround the selected specific point in the unit of a predetermined cellto detect the partial image.

FIG. 4 is a diagram illustrating a camera image captured by a camera.

The camera image illustrated in FIG. 4 is a first image of the camerathat is a line input of camera image for each frame provided from thecamera. Here, a cell area in which the object is positioned among thefirst image may be a partial image.

As illustrated in FIG. 4, the center coordinates B of the first imageand the center coordinates A of the partial image detected from thefirst image are positioned at different points in the first image, andthus do not coincide with each other.

In this case, the camera control apparatus 100 operates to make aspecific point of the object corresponding to the center coordinates Aof the partial image be positioned on the center coordinates of thesecond image corresponding to the subsequent frame.

Although it is preferable to make the specific point of the objectcorresponding to the center coordinates A of the partial image bepositioned on the center coordinates of the second image, it is alsopossible to make a specific point of the object corresponding tospecific coordinates (not illustrated) of the partial image, which isnot the center coordinates A of the partial image, be positioned on thecenter coordinates of the second image.

FIG. 5 is an exemplary diagram illustrating an image screen in theprocess of moving an object in the camera image of FIG. 4 to the centerof a screen.

As illustrated in FIG. 5, in order to make the specific point of theobject corresponding to the center coordinates A of the partial image bepositioned on the center coordinates of the second image, the processor120 gives a weight that makes the control acceleration for movementcontrol of the camera exceed an acceleration of the object to thecontrol acceleration of the camera. According to the movement control ofthe camera, the center coordinates B′ of the second image may bedirected to the specific point of the object corresponding to the centercoordinates A of the partial image that is an image capturing areadifferent from the center coordinates B of the first image.

FIGS. 6 to 8 are exemplary diagrams illustrating the image screen ofFIG. 5 by time zones. FIG. 6 shows a camera image of a frame at time“t”, FIG. 7 shows a camera image of a frame at time “t+1”, and FIG. 8shows a camera image of a frame at time “t+2”.

Referring to FIG. 6, since the center coordinates A of the partial imageincluding the object in the first image coincide with the centercoordinates B of the first image, a separate control for positioning theobject in the center of the screen is not required. That is, if thefirst image is as illustrated in FIG. 6, control center coordinates C ofthe camera is same as the center coordinates A of the partial image andthe center coordinates B of the first image, and thus the second imagethat is a subsequent frame is same as the first image. However, if theobject in the first image is moving, the camera for tracking the objectmoves at the same control acceleration as the acceleration of theobject, and the degree of a background screen in the second image isdifferent from the degree of a background screen in the first image.

Referring to FIG. 7, since the center coordinates A of the partial imageincluding the object in the first image are different from the centercoordinates B of the first image, a separate control for positioning theobject in the center of the screen is required. That is, if the firstimage is as illustrated in FIG. 7, the control center coordinates C ofthe camera may be determined as a specific point in an oppositedirection to the center coordinates A of the partial image based on thecenter coordinates B of the first image.

Further, the processor 120 may determine the acceleration of the objectusing the distance between the center coordinates A of the partial imageand the center coordinates B of the first image, and may determine thecontrol acceleration of the camera using the distance between the centercoordinates A of the partial image and the control center coordinates Cof the camera. If the acceleration of the object using the distancebetween the center coordinates A of the partial image and the centercoordinates B of the first image is “a”, the control acceleration of thecamera using the center coordinates A of the partial image and thecontrol center coordinates C of the camera becomes “2a”. That is, sincethe control acceleration “2a” of the camera is higher than theacceleration (i.e., “a”) of the object, the control speed of the cameramay be set to be higher than the moving speed of the object to make theobject be positioned in the center of the camera as illustrated in FIG.8.

As illustrated in FIG. 8, if the specific point A of the objectcorresponding to the specific coordinates of the partial image ispositioned on the center coordinates B of the second image, theprocessor 120 changes the control acceleration of the camera from “2a”to “a”. Through this, the processor 120 maintains the controlacceleration of the camera and the acceleration of the object equal toeach other.

FIG. 9 is a flowchart illustrating an operation of the processor 120according to an exemplary embodiment.

Referring to FIG. 9, the processor 120 receives camera images in a frameunit from the camera (operation S100). A camera image currently beingreceived is a first image, and a camera image subsequently beingreceived is a second image.

Thereafter, the processor 120 detects the partial image including theobject in the first image through an image detection process (operationS102).

Thereafter, the processor 120 generates a control value for positioningthe specific point of the object corresponding to the specificcoordinates of the partial image detected in operation S102 on thecenter coordinates of the second image which is captured by the camerasubsequent to the first image (operation S104).

Thereafter, the processor 120 outputs the generated control value to thecamera drive controller 130 to make the camera drive controller 130change the image capturing area of the camera (operation S106).

Then, if the camera tracking to track the object in the monitoring areais ended, the above-described steps are all ended (operation S108).

FIG. 10 is a flowchart illustrating of operation S104 shown in FIG. 9,according to an exemplary embodiment.

Referring to FIG. 10, the processor 120 compares the center coordinatesof the first image with the center coordinates of the partial imageincluding the object in the first image (operation S104-1).

Thereafter, the processor 120 determines whether both coordinates do notcoincide with each other (operation S104-3).

If the center coordinates of the first image do not coincide with thecenter coordinates of the partial image including the object in thefirst image, the processor 120 sets the specific point of the firstimage corresponding to the center coordinates of the partial image in anopposite direction to the moving direction of the object as the controlcenter coordinates of the camera (operation S104-5).

Thereafter, the processor 120 gives a weight to the control accelerationof the camera using the distance between the center coordinates of thepartial image and the control center coordinates of the camera(operation S104-7).

Thereafter, the processor 120 generates the control value forcontrolling the driving of the camera based on the weight determined inoperation S104-7, and outputs the generated control value to the cameradrive controller 130 (operation S104-9).

If the center coordinates of the first image coincide with the centercoordinates of the partial image including the object in the firstimage, the object has already been positioned in the center of the imagescreen, and thus the controller 120 maintains the control accelerationof the camera to be equal to the acceleration of the object (operationS104-11).

FIG. 11 is an exemplary diagram illustrating an image screen of anobject which is in a standstill state or of which the direction ischanged in the camera image of FIG. 4, according to an exemplaryembodiment.

The processor 120 controls the movement of the camera by increasing themoving speed of the camera to make the object be always positioned inthe camera image, and then performs a control so as to remove a screenvibration phenomenon that occurs in the center portion of the cameraimage due to inertia of movement of the camera, that is caused by acamera stop when the object being tracked is stopped or changes itsdirection.

For example, two control methods for the processor 120 to remove thescreen vibration phenomenon may be performed.

As a first method, the processor 120 may predetermine a speed reductionpattern of the acceleration of the object, set a speed reduction sectionof the camera before a stop expectation point of the object, and executea speed reduction process to minimize the inertia of movement of thecamera in the set speed reduction section.

As a second method, if the speed reduction pattern of the accelerationof the object does not exist, the processor 120 may set the speedreduction section of the camera based on the stop point of the objectduring the stop or direction change of the object, and move the camerain a reverse direction at a predetermined reference speed as long as adistance between the center coordinates B of the camera image asillustrated in FIG. 11 and the specific point of the object.

The predetermined reference speed is a moving speed for positioning theobject in the center of the screen after temporarily stopping themovement of the camera that tracks the object, and it is preferable, butnot necessary, that the predetermined reference speed is a speed thatminimizes the inertia of movement of the camera even if the camera isstopped after moving as long as the distance between the centercoordinates B of the camera image and the specific point of the object.

Further, even if the control acceleration of the camera is abruptlychanged to the acceleration of the object, the processor 120 can operateto remove the screen vibration phenomenon as described above.

FIG. 12 is a flowchart illustrating a process subsequent to “K” shown inFIG. 10, according to an exemplary embodiment.

Referring to FIG. 12, the processor 120 determines whether a speedreduction pattern of the acceleration of the object exists duringmovement control of the camera to track the object (operation S104-13).

If it is determined that the speed reduction pattern of the accelerationof the object exists, the processor 120 sets a speed reduction sectionof the camera in the moving direction of the object (operation S104-15).

Thereafter, if the camera enters into the speed reduction section, theprocessor 120 removes a weight that is given to the control accelerationof the camera (operation S104-17).

Thereafter, the processor 120 sets the control acceleration of thecamera to be equal to the acceleration of the object to minimize theinertia of movement of the camera (operation S104-19).

If it is determined that the speed reduction pattern of the accelerationof the object does not exist, the processor 120 determines whether theobject is stopped or changes its direction (operation S104-21).

If it is determined that the object is stopped or changes its direction,the processor 120 sets the speed reduction section of the camera basedon the stopping point of the object (operation S104-23).

Thereafter, the processor 120 controls the camera (not illustrated) tobe gradually stopped in the speed reduction section of S104-23(operation S104-25).

Thereafter, the processor 120 sets to move the camera in a reversedirection at a reference speed as long as the distance between thecenter coordinates of the partial image including the object positionedin a reverse direction to the traveling direction of the camera and thecenter coordinates of the camera image (operation S104-27).

FIG. 13 is an exemplary diagram illustrating camera images captured by acamera, which are discriminated by control directions.

Referring to FIG. 13, the control center coordinates of the camera arechanged with directivity according to the control direction of thecamera to track the object.

FIG. 14 is an exemplary diagram illustrating an example in which anobject is specified if a plurality of objects exist in a camera imagecaptured by a camera.

Referring to FIG. 14, a plurality of objects may exist in the firstimage. In this case, the processor 120 may set a moving object in thefirst image as a target.

FIG. 15 is a flowchart illustrating an operation of the camera controlapparatus 100 of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 15, the processor 120 receives camera images in aframe unit from the camera (operation S200). A camera image currentlybeing received is a first image, and a camera image subsequently beingreceived is a second image.

Thereafter, the processor 120 detects the partial image including theobject from the first image through an image detection process, and if aplurality of objects exist in the first image, the processor 120 sets amoving object as a target (operation S202).

Thereafter, the processor 120 generates a control value for positioningthe specific point of the object corresponding to the specificcoordinates of the partial image detected in operation S202 on thecenter coordinates of the second image which is captured by the camerasubsequent to the first image (operation S204).

Thereafter, the processor 120 outputs the generated control value to thecamera drive controller 130 to make the camera drive controller 130change the image capturing area of the camera (operation S206).

Then, if the camera tracking to track the object in the monitoring areais ended, the above-described steps are all ended (operation S208).

FIG. 16 is an exemplary diagram illustrating another example in which anobject is specified if a plurality of objects exist in a camera imagecaptured by a camera.

Referring to FIG. 16, if a plurality of objects exist in the first imageand a plurality of objects are moving, the processor 120 may specify anobject selected by a user or may select any one object of the pluralityof objects according to a predetermined selection priority.

FIG. 17 is a flowchart illustrating an operation of the camera controlapparatus 100 of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 17, the processor 120 receives camera images in aframe unit from the camera (operation S300). A camera image currentlybeing received is a first image, and a camera image subsequently beingreceived is a second image.

Thereafter, the processor 120 detects the partial image including theobject in the first image through an image detection process, and if aplurality of objects exist in the first image, the processor 120 outputsa notification message for notifying a user thereof (operations S302 toS304).

The user who is a manager selects any one of the plurality of objects inthe first image (operation S306).

The processor 120 sets the object selected by the user as a target(operation S308).

Thereafter, the processor 120 generates a control value for positioningthe specific point of the object corresponding to the specificcoordinates of the partial image detected in operation 308 on the centercoordinates of the second image which is captured by the camerasubsequent to the first image (operation S310).

Thereafter, the processor 120 outputs the generated control value to thecamera drive controller 130 to make the camera drive controller 130change the image capturing area of the camera (operation S312).

Then, if the camera tracking to track the object in the monitoring areais ended, the above-described steps are all ended (operation S314).

FIG. 18 is a flowchart illustrating an operation of the camera controlapparatus 100 of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 18, the processor 120 receives camera images in aframe unit from the camera (operation S400). A camera image currentlybeing received is a first image, and a camera image subsequently beingreceived is a second image.

Thereafter, the processor 120 detects the partial image including theobject in the first image through an image detection process, and if aplurality of objects exist in the first image, the processor 120 mayselect an object having high possibility of seceding from the monitoringarea as a priority object (operations S402 to S406).

Thereafter, the processor 120 generates a control value for positioningthe specific point of the object corresponding to the specificcoordinates of the partial image detected in operations 406 on thecenter coordinates of the second image which is captured by the camerasubsequent to the first image (operation S408).

Thereafter, the processor 120 outputs the generated control valuegenerated to the camera drive controller 130 to make the camera drivecontroller 130 change the image capturing area of the camera (operationS410).

Then, if the camera tracking to track the object in the monitoring areais ended, the above-described steps are all ended (operation S412).

FIG. 19 is an exemplary diagram illustrating a case where objects recedein the distance in camera images captured by a camera.

It is preferable, but not necessary, that the camera control apparatus100 is configured so that objects included in camera images obtained bycapturing a monitoring area are always positioned in the center of thecamera images even if a zoom magnification is changed.

Referring to FIG. 19, if the zoom magnification is not changed in thecase where objects recede in the distance in camera images that movefrom left to right, the fields of view of the respective camera imagesare kept as they are. In FIG. 19, the fields of view of the respectivecamera images are all 55.5°.

If zoom-in is performed in the camera, the field of view (FOV) withrespect to the screen is narrowed, while if zoom-out is performed, theFOV with respect to the screen is widened.

The FOV is obtained by Equation 1 below.FOV=2 arctan (0.5 h/f),  [Equation 1]where, h is a sensor size, and f is a focal length.

Further, in the case of calculating the control value using onlyproportional-integral-derivative (PID) control, a problem may occur in amethod using an accumulated average.

That is, if the same acceleration is applied if the size of the objectappears the same as the zoom magnification is changed, the control isperformed at an improper speed (e.g., too fast or too slow).

However, according to the exemplary embodiment, since the actualacceleration is not accumulatively averaged, but the accumulated averageis calculated through movement of the center of the control on thescreen, the change of the control of the zoom magnification is reflectedin the FOV, and the acceleration per pixel is immediately changed.

That is, the change of the accumulated average of the accelerationaccording to the change of zoom magnification can be solved through themovement of the center of the control.

FIG. 20 is an exemplary diagram illustrating zoom-in camera images ofFIG. 19.

Referring to FIG. 20, respective camera images are images that areobtained by performing zoom-in or non-zoom-in with respect to the cameraimages of FIG. 19.

In FIG. 20, the second camera image corresponds to a case where the FOVis changed from 55.5° to 35° as a result of performing the zoom-in withrespect to the second camera image of FIG. 19.

In FIG. 20, the fifth camera image corresponds to a case where the FOVis changed from 55.5° to 1.59° as a result of performing the zoom-inwith respect to the fifth camera image of FIG. 19.

FIGS. 21A and 21B are exemplary diagrams illustrating respective imagesthat are obtained by discriminating camera images of FIG. 4 according tofields of view.

FIG. 21A shows a camera image obtained through moving the camera imageof FIG. 4 as it is, and the zoom magnification is not changed. That is,the FOV is 55°.

FIG. 21B shows a case where the zoom magnification is changed throughperforming of the zoom-in with respect to the camera image of FIG. 4.That is, the FOV is 1.59°.

Referring to FIGS. 21A and 21B, although the respective camera imageshave different FOV, the distances between the screen center and thecontrol center are same. In this case, if the control speed includes theaccumulated average, the speed change that is confirmed in thecorresponding camera image becomes too fast when the zoom magnificationis changed (e.g., the zoom-in is performed) as shown in FIG. 21B.

Accordingly, the control value calculation module makes the object inthe camera image be always positioned in the center of the screen evenif the zoom magnification is changed by generating a control valueincluding the FOV value according to the zoom magnification applied tothe camera image as a parameter to be applied to the weight change ofthe control acceleration for movement of the camera.

FIG. 22 is a graph illustrating an example of an acceleration changeaccording to a zoom change.

Referring to FIG. 22, the acceleration may be changed as in Equation 2and Equation 3 below according to the zoom magnification.P_Spd1=arctan (avg_spd/D1),  [Equation 2]where P_Spd1 is an acceleration in the case of a first zoommagnification, avg_spd is an average moving speed of an object, and D1is a first distance between a camera and an object.P_Spd2=arctan (avg_spd/D2),  [Equation 3]where P_Spd2 is an acceleration in the case of a second zoommagnification, avg_spd is an average moving speed of an object, and D2is a second distance between a camera and an object.

For example, if D1 is the FOV corresponding to FIG. 21B and D2 is theFOV corresponding to FIG. 21A, the first acceleration P_Spd1 and thesecond acceleration P_Spd2 are calculated as described above. In thiscase, the speed change during the change of zoom magnification becomesgreat, and the control value calculation module generates the controlvalue including the FOV value according to the zoom magnificationapplied to the camera image as a parameter to be applied to the weightchange of the control acceleration for the movement of the camera.

For example, the control value calculation module can set the controlacceleration corresponding to FIG. 21B, which is different from thecontrol acceleration corresponding to FIG. 21A, using the deviationbetween the FOA corresponding to FIG. 21A and the FOA corresponding toFIG. 21B.

At least one of the components, elements, modules or units representedby a block as illustrated in FIGS. 1-3 may be embodied as variousnumbers of hardware, software and/or firmware structures that executerespective functions described above, according to an exemplaryembodiment. For example, at least one of these components, elements,modules or units may use a direct circuit structure, such as a memory,processing, logic, a look-up table, etc. that may execute the respectivefunctions through controls of one or more microprocessors or othercontrol apparatuses. Also, at least one of these components, elements,modules or units may be specifically embodied by a module, a program, ora part of code, which contains one or more executable instructions forperforming specified logic functions. Also, at least one of thesecomponents, elements, modules or units may further include a processorsuch as a central processing unit (CPU) that performs the respectivefunctions, a microprocessor, or the like. Further, although a bus is notillustrated in the above block diagrams, communication between thecomponents, elements, modules or units may be performed through the bus.

According to the exemplary embodiments, since the object included in thecamera image obtained by capturing an image of the monitoring area isalways positioned in the center of the camera image, the inventiveconcept can be embodied with possibility of marketing and trade, andthus becomes industrially applicable.

Although the exemplary embodiments have been described for illustrativepurposes, those skilled in the art will appreciate that variousmodifications, additions and substitutions are possible, withoutdeparting from the scope and spirit of the inventive concept asdisclosed in the accompanying claims.

What is claimed is:
 1. A camera control apparatus comprising: a processor configured to detect a partial image including an object from a first image of a camera, generate a control value for controlling a camera capturing area to position a specific point of the object corresponding to specific coordinates of the partial image on center coordinates of a second image of the camera which is captured by the camera subsequent to the first image, based on center coordinates of the partial image and center coordinates of the first image; and a camera drive controller configured to change the camera capturing area based on the control value output from the processor, wherein if the center coordinates of the partial image do not coincide with the center coordinates of the first image, the processor sets a specific point in the first image, which is opposite to the center coordinates of the partial image with respect to the center coordinates of the first image, as control center coordinates of the camera in the first image, calculates a distance between the center coordinates of the partial image and the control center coordinates of the camera in the first image, generates a weight, that makes a control acceleration for movement control of the camera exceed an acceleration of the object, based on the calculated distance, and gives the weight to a control acceleration of the camera, thereby generating the control value, wherein the processor is further configured to determine whether a speed reduction pattern of the acceleration of the object exists, and, if it is determined that the speed reduction pattern exists, set a camera moving speed reduction section in a moving direction of the object before a stop expectation point of the object, and wherein after setting the camera moving speed reduction section, the processor removes or changes the weight given to the control acceleration of the camera.
 2. The camera control apparatus of claim 1, further comprising at least one memory configured to store program code, wherein the processor is further configured to be instructed by the program code, the program code comprising: an image reception code that causes the processor to receive a camera image in a frame unit; a target detection code that causes the processor to detect the partial image through a user's selection or a predetermined image detection process; a control value calculation code that causes the processor to determine the control center coordinates of the camera in the first image, and change a given weight for the control acceleration of the camera for changing the camera capturing area according to the distance between the center coordinates of the partial image and the control center coordinates of the camera in the first image, and generate the control value based on the changed weight; and a control execution code that causes the processor to output the control value to the camera drive controller.
 3. The camera control apparatus of claim 2, further comprising an inputter to select the partial image.
 4. The camera control apparatus of claim 1, wherein if it is determined that the speed reduction pattern does not exist the processor determines whether the object stops or changes the moving direction, and, if it is determined that the object stops or changes the moving direction, sets the camera speed reduction section based on a stop point of the object during the stop or the moving direction change of the object, determines whether the object is positioned at a specific point behind center coordinates of a third image, captured at a time of the stop or the moving direction change, with respect to the moving direction of the object, and, if it is determined that the object is positioned at the specific point behind the center coordinates of the image, controls the camera drive controller to move the camera in a direction opposite to the moving direction of the object at a predetermined reference speed as long as a distance between the center coordinates of the third image and center coordinates of the object in the third image.
 5. The camera control apparatus of claim 2, wherein if a plurality of objects exist in the first image, the target detection code causes the processor to select any one of the plurality of objects by a user selection.
 6. The camera control apparatus of claim 2, wherein if a plurality of objects exist in the first image, the target detection code causes the processor to automatically select any one of the plurality of objects based on a predetermined selection priority, in which an object having high possibility of seceding from a monitoring area is set as a priority object.
 7. The camera control apparatus of claim 2, wherein the control value calculation code causes the processor to include parameters for applying a field of view (FOV) value corresponding to a zoom magnification of the second image to the weight change of the control acceleration.
 8. A method of controlling a camera control apparatus comprising: receiving a camera image in a frame unit from a camera; detecting a partial image including an object from a first image of the camera; generating a control value for controlling a camera capturing area to position a specific point of the object corresponding to specific coordinates of the partial image on center coordinates of a second image of the camera which is captured by the camera subsequent to the first image based on center coordinates of the partial image and center coordinates of the first image; and changing the camera capturing area based on the generated control value, wherein the generating the control value comprises if the center coordinates of the partial image do not coincide with the center coordinates of the first image, setting a specific point in the first image, which is opposite to the center coordinates of the partial image with respect to the center coordinates of the first image, as control center coordinates of the camera in the first image, calculating a distance between the center coordinates of the partial image and the control center coordinates of the camera in the first image, generating a weight, that makes a control acceleration for movement control of the camera exceed an acceleration of the object, based on the calculated distance, and giving the weight to a control acceleration of the camera, thereby generating the control value, wherein the method further comprises: determining whether a speed reduction pattern of the acceleration of the object exists during a movement control of the camera; if it is determined that the speed reduction pattern exists, setting a camera moving speed reduction section in a moving direction of the object before a stop expectation point of the object; and after setting the camera moving speed reduction section, removing or changing the weight given to the control acceleration of the camera.
 9. The method of claim 8, wherein the detecting the partial image is performed through a user's selection or a predetermined image detection process.
 10. The method of claim 8, wherein the generating the control value comprises: comparing center coordinates of the partial image with center coordinates of the first image; determining whether both coordinates do not coincide with each other; if it is determined that both coordinates do not coincide with each other, determining the control center coordinates of the camera in the first image and changing a given weight for the control acceleration of the camera for changing the camera according to the distance between the center coordinates of the partial image and the control center coordinates of the camera in the first image.
 11. The method of claim 10, wherein if it is determined that both coordinates coincide with each other, setting the control acceleration of the camera using a distance between the center coordinates of the partial image and the control center coordinates of the camera in the first image to be equal to an acceleration of the object using a distance between the center coordinates of the partial image and the center coordinates of the first image.
 12. The method of claim 8, wherein if it is determined that the speed reduction pattern does not exist, determining whether the object stops or changes the moving direction, and, if it is determined that the object stops or changes the moving direction, setting the camera speed reduction section based on a stop point of the object during the stop or the moving direction change of the object, determining whether the object is positioned at a specific point behind center coordinates of a third image, captured at a time of the stop or the moving direction change, with respect to the moving direction of the object, and, if it is determined that the object is positioned at the specific point behind the center coordinates of the image, setting to move camera in a direction opposite to the moving direction of the object at a predetermined reference speed as long as a distance between the center coordinates of the third image and center coordinates of the object in the third image.
 13. The method of claim 8, wherein if a plurality of objects exist in the first image, the detecting the partial image comprises selecting any one of the plurality of objects by a user selection.
 14. The method of claim 8, wherein if a plurality of objects exist in the first image, the detecting the partial image comprises selecting any one of the plurality of objects based on a predetermined selection priority, in which an object having high possibility of seceding from a monitoring area is set as a priority object.
 15. The method of claim 10, the generating the control value comprises generating the control value including parameters for applying a field of view (FOV) value corresponding to a zoom magnification of the second image to the weight change of the control acceleration.
 16. A non-transitory computer readable medium having recorded thereon a program, which, when executed by a computer, performs the method of claim
 8. 